You don't mention which software release you are running on your SX20, so I will comment on the behaviour of the current CE9.4.0 release:
You can change the layout of what is sent to the far end of the conference by changing the "Video DefaultLayoutFamily Remote" setting on the SX (See page 145 of the CE9.4.0 Admin Guide).
Value space: Auto/Equal/Prominent/Overlay/Single
Auto: The default layout family, as given by the local layout database, will be used as the remote layout. Equal: The Equal layout family will be used as the remote layout. All videos have equal size, as long as there is space enough on the screen.
Prominent: The Prominent layout family will be used as the remote layout. The active speaker, or the presentation if present, will be a large picture, while the other participants will be small pictures. Transitions between active speakers are voice switched.
Overlay: The Overlay layout family will be used as the remote layout. The active speaker, or the presentation if present, will be shown in full screen, while the other participants will be small pictures-in-picture (PiP). Transitions between active speakers are voice switched.
Single: The other participants are not shown. Transitions between active speakers are voice switched.
Wayne
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